/Engine/Source/Developer/ShaderCompilerCommon/Public/ShaderConductorContext.h
Returns a filename extension for the specified shading language and shader stage, e.g. "frag" for a GLSL pixel shader.
static const TCHAR * GetShaderFileExt ( [EShaderConductorLanguage](API\Developer\ShaderCompilerCommon\CrossCompiler__EShaderConductorL-) Language, EShaderFrequency ShaderStage )